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Gassiep I, Burnard D, Bauer MJ, Norton RE, Harris PN. Diagnosis of melioidosis: the role of molecular techniques. Future Microbiol 2021; 16:271-288. [PMID: 33595347 DOI: 10.2217/fmb-2020-0202] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Melioidosis is an emerging infectious disease with an estimated global burden of 4.64 million disability-adjusted life years per year. A major determinant related to poor disease outcomes is delay to diagnosis due to the fact that identification of the causative agent Burkholderia pseudomallei may be challenging. Over the last 25 years, advances in molecular diagnostic techniques have resulted in the potential for rapid and accurate organism detection and identification direct from clinical samples. While these methods are not yet routine in clinical practice, laboratory diagnosis of infectious diseases is transitioning to culture-independent techniques. This review article aims to evaluate molecular methods for melioidosis diagnosis direct from clinical samples and discuss current and future utility and limitations.
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Affiliation(s)
- Ian Gassiep
- University of Queensland Centre for Clinical Research, Royal Brisbane and Woman's Hospital, Herston, Queensland, 4029, Australia.,Department of Infectious Diseases, Mater Hospital Brisbane, South Brisbane, Queensland, 4101, Australia
| | - Delaney Burnard
- University of Queensland Centre for Clinical Research, Royal Brisbane and Woman's Hospital, Herston, Queensland, 4029, Australia
| | - Michelle J Bauer
- University of Queensland Centre for Clinical Research, Royal Brisbane and Woman's Hospital, Herston, Queensland, 4029, Australia
| | - Robert E Norton
- Pathology Queensland, Townsville University Hospital, Townsville, Queensland, 4814, Australia
| | - Patrick N Harris
- University of Queensland Centre for Clinical Research, Royal Brisbane and Woman's Hospital, Herston, Queensland, 4029, Australia.,Pathology Queensland, Royal Brisbane & Women's Hospital, Herston, Queensland, 4029, Australia
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Bandeira TDJPG, Castelo-Branco DDSCM, Rocha MFG, Cordeiro RDA, Ocadaque CJ, Paiva MDAN, Brilhante RSN, Sidrim JJC. Clinical and environmental isolates of Burkholderia pseudomallei from Brazil: Genotyping and detection of virulence gene. ASIAN PAC J TROP MED 2017; 10:945-951. [PMID: 29111189 DOI: 10.1016/j.apjtm.2017.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 08/13/2017] [Accepted: 09/11/2017] [Indexed: 10/18/2022] Open
Abstract
OBJECTIVE To evaluate the genetic diversity of clinical and environmental isolates of Burkholderia pseudomallei (B. pseudomallei) recovered in Ceará, Brazil, and screen these isolates for the presence of type three secretion system virulence gene. METHODS Nineteen B. pseudomallei isolates (9 from clinical cases and 10 from soils) were analyzed. Random amplified polymorphic DNA was performed with primers OPQ-2, OPQ-4 and OPQ-16 to evaluate the genetic diversity, and type three secretion system gene was detected through polymerase chain reaction. RESULTS Random amplified polymorphic DNA showed a genetic relatedness of approximately 50% among the tested B. pseudomallei isolates, which were grouped into two clades, of which the biggest ones comprised 18/19 isolates for primer OPQ-2, and 17/19 isolates for primer OPQ-16. Primer OPQ-4 grouped the isolates into three clades comprising 1/19, 3/19 and 15/19 isolates. Additionally, type three secretion system gene was detected in all tested isolates. CONCLUSIONS This is an effort to type B. pseudomallei strains from Ceará, which is important for better understanding this pathogen, contributing for the epidemiological surveillance of melioidosis in this endemic region.
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Affiliation(s)
- Tereza de Jesus Pinheiro Gomes Bandeira
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Federal University of Ceará, Fortaleza, Ceará, Brazil; Christus School of Medicine, Fortaleza, Ceará, Brazil
| | | | - Marcos Fábio Gadelha Rocha
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Federal University of Ceará, Fortaleza, Ceará, Brazil; Postgraduate Program in Veterinary Sciences, State University of Ceará, Fortaleza, Ceará, Brazil
| | - Rossana de Aguiar Cordeiro
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Crister José Ocadaque
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Manoel de Araújo Neto Paiva
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Federal University of Ceará, Fortaleza, Ceará, Brazil; Federal Institute of Education, Science and Technology of Ceará, Acaraú, Ceará, Brazil
| | - Raimunda Sâmia Nogueira Brilhante
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Federal University of Ceará, Fortaleza, Ceará, Brazil.
| | - José Júlio Costa Sidrim
- Specialized Medical Mycology Center, Postgraduate Program in Medical Microbiology, Federal University of Ceará, Fortaleza, Ceará, Brazil
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Monecke S, Friedrichs A, Pöhlmann C, Hochauf K, Gunzer F, Wiesner D, Sickert W, Steinmetz I, Scholz H, Ehricht R, Schmoock G, Jacobs E. An imported case of melioidosis presenting as pyelonephritis/urosepsis. JMM Case Rep 2015. [DOI: 10.1099/jmmcr.0.000073] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Stefan Monecke
- Alere Technologies GmbH, Löbstedter Strasse 103-105, D-07749 Jena, Germany
- Institute for Medical Microbiology and Hygiene, Technische Universität Dresden, Fetscherstrasse 74, D-01307 Dresden, Germany
| | - Anette Friedrichs
- Department of Internal Medicine I, University Hospital Schleswig-Holstein, Campus Kiel, Schittenhelmstrasse12, D-24105 Kiel, Germany
| | - Christoph Pöhlmann
- Department of Laboratory Medicine, Robert-Bosch-Hospital, Auerbachstraße 110, D-70376 Stuttgart, Germany
| | - Kristina Hochauf
- Institute for Medical Microbiology and Hygiene, Technische Universität Dresden, Fetscherstrasse 74, D-01307 Dresden, Germany
| | - Florian Gunzer
- Institute for Medical Microbiology and Hygiene, Technische Universität Dresden, Fetscherstrasse 74, D-01307 Dresden, Germany
| | - Diana Wiesner
- Deaconesses' Hospital Dessau, Gropiusallee 3, D-06846 Dessau-Roßlau, Germany
| | | | - Ivo Steinmetz
- Friedrich-Loeffler-Institute for Medical Microbiology, University of Greifswald, Lutherstrasse 6, D-17489 Greifswald, Germany
| | - Holger Scholz
- Bundeswehr Institute of Microbiology, Neuherbergstrasse 11, D-80937 Munich, Germany
- German Center for Infection Research (DZIF), Munich, Germany
| | - Ralf Ehricht
- Alere Technologies GmbH, Löbstedter Strasse 103-105, D-07749 Jena, Germany
| | - Gernot Schmoock
- Friedrich Loeffler Institute, Institute of Bacterial Infections and Zoonoses, Naumburger Strasse 96a, D-07743 Jena, Germany
| | - Enno Jacobs
- Institute for Medical Microbiology and Hygiene, Technische Universität Dresden, Fetscherstrasse 74, D-01307 Dresden, Germany
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Antonov VA, Tkachenko GA, Altukhova VV, Savchenko SS, Zinchenko OV, Viktorov DV, Zamaraev VS, Ilyukhin VI, Alekseev VV. Molecular identification and typing of Burkholderia pseudomallei and Burkholderia mallei: when is enough enough? Trans R Soc Trop Med Hyg 2008; 102 Suppl 1:S134-9. [DOI: 10.1016/s0035-9203(08)70030-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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5
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Leveau JHJ, Preston GM. Bacterial mycophagy: definition and diagnosis of a unique bacterial-fungal interaction. THE NEW PHYTOLOGIST 2008; 177:859-876. [PMID: 18086226 DOI: 10.1111/j.1469-8137.2007.02325.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
This review analyses the phenomenon of bacterial mycophagy, which we define as a set of phenotypic behaviours that enable bacteria to obtain nutrients from living fungi and thus allow the conversion of fungal into bacterial biomass. We recognize three types of bacterial strategies to derive nutrition from fungi: necrotrophy, extracellular biotrophy and endocellular biotrophy. Each is characterized by a set of uniquely sequential and differently overlapping interactions with the fungal target. We offer a detailed analysis of the nature of these interactions, as well as a comprehensive overview of methodologies for assessing and quantifying their individual contributions to the mycophagy phenotype. Furthermore, we discuss future prospects for the study and exploitation of bacterial mycophagy, including the need for appropriate tools to detect bacterial mycophagy in situ in order to be able to understand, predict and possibly manipulate the way in which mycophagous bacteria affect fungal activity, turnover, and community structure in soils and other ecosystems.
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Affiliation(s)
- Johan H J Leveau
- Netherlands Institute of Ecology (NIOO-KNAW), Heteren, the Netherlands
| | - Gail M Preston
- Department of Plant Sciences, University of Oxford, Oxford, UK
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Kaestli M, Mayo M, Harrington G, Watt F, Hill J, Gal D, Currie BJ. Sensitive and specific molecular detection of Burkholderia pseudomallei, the causative agent of melioidosis, in the soil of tropical northern Australia. Appl Environ Microbiol 2007; 73:6891-7. [PMID: 17873073 PMCID: PMC2074964 DOI: 10.1128/aem.01038-07] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Burkholderia pseudomallei, the cause of the severe disease melioidosis in humans and animals, is a gram-negative saprophyte living in soil and water of areas of endemicity such as tropical northern Australia and Southeast Asia. Infection occurs mainly by contact with wet contaminated soil. The environmental distribution of B. pseudomallei in northern Australia is still unclear. We developed and evaluated a direct soil B. pseudomallei DNA detection method based on the recently published real-time PCR targeting the B. pseudomallei type III secretion system. The method was evaluated by inoculating different soil types with B. pseudomallei dilution series and by comparing B. pseudomallei detection rate with culture-based detection rate for 104 randomly collected soil samples from the Darwin rural area in northern Australia. We found that direct soil B. pseudomallei DNA detection not only was substantially faster than culture but also proved to be more sensitive with no evident false-positive results. This assay provides a new tool to detect B. pseudomallei in soil samples in a fast and highly sensitive and specific manner and is applicable for large-scale B. pseudomallei environmental screening studies or in outbreak situations. Furthermore, analysis of the 104 collected soil samples revealed a significant association between B. pseudomallei-positive sites and the presence of animals at these locations and also with moist, reddish brown-to-reddish gray soils.
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Affiliation(s)
- Mirjam Kaestli
- Tropical and Emerging Infectious Diseases Division, Menzies School of Health Research, Charles Darwin University, PO Box 41096, Casuarina, Northern Territory 0811, Australia
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Ekpo P, Rungpanich U, Pongsunk S, Naigowit P, Petkanchanapong V. Use of protein-specific monoclonal antibody-based latex agglutination for rapid diagnosis of Burkholderia pseudomallei infection in patients with community-acquired septicemia. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2007; 14:811-2. [PMID: 17428952 PMCID: PMC1951097 DOI: 10.1128/cvi.00011-07] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A latex agglutination test employing monoclonal antibody specific to a 30-kDa protein of Burkholderia pseudomallei was used to detect the organisms in blood culture specimens from 1,139 patients with community-acquired septicemia. The sensitivity, specificity, and positive and negative predictive values of the test were 96.75%, 99.61%, 96.75%, and 99.61%, respectively.
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Affiliation(s)
- Pattama Ekpo
- Department of Immunology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
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Duangsonk K, Gal D, Mayo M, Hart CA, Currie BJ, Winstanley C. Use of a variable amplicon typing scheme reveals considerable variation in the accessory genomes of isolates of Burkholderia pseudomallei. J Clin Microbiol 2006; 44:1323-34. [PMID: 16597858 PMCID: PMC1448637 DOI: 10.1128/jcm.44.4.1323-1334.2006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Melioidosis, a disease caused by the bacterium Burkholderia pseudomallei, is endemic in southeast Asia and northern Australia. We used suppression subtractive hybridization (SSH) to identify sequences that varied between two B. pseudomallei isolates from Australia and determined the distribution of 45 SSH-derived sequences among a panel of B. pseudomallei and B. thailandensis isolates. Sequences exhibiting variable prevalence were included in a variable amplicon typing (VAT) scheme designed to score the presence or absence of 14 PCR amplicons. VAT analysis was carried out with 48 isolates from Thailand, which were typed by multilocus sequence typing (MLST), and 44 isolates from Australia of known MLST type. The VAT scheme could be used to divide the 48 isolates from Thailand into 23 VAT types and the 44 isolates from Australia into 36 VAT types. Some of the sequences included in the VAT scheme were more commonly PCR positive among isolates from Australia than among isolates from Thailand, and vice versa. No isolate from Australia was PCR positive for genomic island 11 or a putative transposase sequence, whereas four SSH-derived sequences were far more prevalent among the Australian isolates. Analysis based on the VAT scheme indicated that the isolates clustered into groups, some of which were mainly or exclusively from one geographical origin. One cluster included Australian isolates that were mostly associated with severe disease, including rare neurological melioidosis, suggesting that the content of the accessory genome may play an important role in determining the clinical manifestation of the disease.
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Affiliation(s)
- Kwanjit Duangsonk
- Division of Medical Microbiology, University of Liverpool, Duncan Building, Daulby Street, Liverpool L69 3GA, United Kingdom.
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Novak RT, Glass MB, Gee JE, Gal D, Mayo MJ, Currie BJ, Wilkins PP. Development and evaluation of a real-time PCR assay targeting the type III secretion system of Burkholderia pseudomallei. J Clin Microbiol 2006; 44:85-90. [PMID: 16390953 PMCID: PMC1351940 DOI: 10.1128/jcm.44.1.85-90.2006] [Citation(s) in RCA: 149] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Here we report on the development of a discriminatory real-time assay for the rapid identification of Burkholderia pseudomallei isolates and the evaluation of this assay for sensitivity against related species and detection in spiked human blood samples. The assay targets a 115-base-pair region within orf2 of the B. pseudomallei type III secretion system gene cluster and distinguishes B. pseudomallei from other microbial species. Assay performance was evaluated with 224 geographically, temporally, and clinically diverse B. pseudomallei isolates from the Centers for Disease Control and Prevention strain collection. This represents the first real-time PCR for rapid and sensitive identification of B. pseudomallei that has been tested for cross-reactivity with 23 Burkholderia mallei, 5 Burkholderia thailandensis, and 35 Burkholderia and 76 non-Burkholderia organisms which have historically presented diagnostic challenges. The assay performed with 100% specificity. The limit of detection was found to be 76 femtograms of DNA (equivalent to 5.2 x 10(3) genome equivalents per ml) in a single PCR. In spiked human blood, the assay could detect as few as 8.4 x 10(3) CFU per ml. This rapid assay is a valuable tool for identification of B. pseudomallei and may improve diagnosis in regions endemic for melioidosis.
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Affiliation(s)
- Ryan T Novak
- Meningitis and Special Pathogens Branch, Division of Bacterial and Mycotic Diseases, National Center for Infectious Diseases, CDC, Atlanta, GA 30333, USA
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Abstract
Melioidosis, caused by the gram-negative saprophyte Burkholderia pseudomallei, is a disease of public health importance in southeast Asia and northern Australia that is associated with high case-fatality rates in animals and humans. It has the potential for epidemic spread to areas where it is not endemic, and sporadic case reports elsewhere in the world suggest that as-yet-unrecognized foci of infection may exist. Environmental determinants of this infection, apart from a close association with rainfall, are yet to be elucidated. The sequencing of the genome of a strain of B. pseudomallei has recently been completed and will help in the further identification of virulence factors. The presence of specific risk factors for infection, such as diabetes, suggests that functional neutrophil defects are important in the pathogenesis of melioidosis; other studies have defined virulence factors (including a type III secretion system) that allow evasion of killing mechanisms by phagocytes. There is a possible role for cell-mediated immunity, but repeated environmental exposure does not elicit protective humoral or cellular immunity. A vaccine is under development, but economic constraints may make vaccination an unrealistic option for many regions of endemicity. Disease manifestations are protean, and no inexpensive, practical, and accurate rapid diagnostic tests are commercially available; diagnosis relies on culture of the organism. Despite the introduction of ceftazidime- and carbapenem-based intravenous treatments, melioidosis is still associated with a significant mortality attributable to severe sepsis and its complications. A long course of oral eradication therapy is required to prevent relapse. Studies exploring the role of preventative measures, earlier clinical identification, and better management of severe sepsis are required to reduce the burden of this disease.
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Affiliation(s)
- Allen C Cheng
- Menzies School of Health Research, Charles Darwin University, Darwin, Australia
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Pallen MJ, Beatson SA, Bailey CM. Bioinformatics, genomics and evolution of non-flagellar type-III secretion systems: a Darwinian perpective. FEMS Microbiol Rev 2005; 29:201-29. [PMID: 15808742 DOI: 10.1016/j.femsre.2005.01.001] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2004] [Revised: 12/22/2004] [Accepted: 01/06/2005] [Indexed: 12/17/2022] Open
Abstract
We review the biology of non-flagellar type-III secretion systems from a Darwinian perspective, highlighting the themes of evolution, conservation, variation and decay. The presence of these systems in environmental organisms such as Myxococcus, Desulfovibrio and Verrucomicrobium hints at roles beyond virulence. We review newly discovered sequence homologies (e.g., YopN/TyeA and SepL). We discuss synapomorphies that might be useful in formulating a taxonomy of type-III secretion. The problem of information overload is likely to be ameliorated by launch of a web site devoted to the comparative biology of type-III secretion ().
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Affiliation(s)
- Mark J Pallen
- Bacterial Pathogenesis and Genomics Unit, Division of Immunity and Infection, Medical School, University of Birmingham, Birmingham, West Midlands B15 2TT, UK.
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Cheng AC, Currie BJ. Melioidosis: epidemiology, pathophysiology, and management. Clin Microbiol Rev 2005. [PMID: 15831829 DOI: 10.1128/cmr.18.2.383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023] Open
Abstract
Melioidosis, caused by the gram-negative saprophyte Burkholderia pseudomallei, is a disease of public health importance in southeast Asia and northern Australia that is associated with high case-fatality rates in animals and humans. It has the potential for epidemic spread to areas where it is not endemic, and sporadic case reports elsewhere in the world suggest that as-yet-unrecognized foci of infection may exist. Environmental determinants of this infection, apart from a close association with rainfall, are yet to be elucidated. The sequencing of the genome of a strain of B. pseudomallei has recently been completed and will help in the further identification of virulence factors. The presence of specific risk factors for infection, such as diabetes, suggests that functional neutrophil defects are important in the pathogenesis of melioidosis; other studies have defined virulence factors (including a type III secretion system) that allow evasion of killing mechanisms by phagocytes. There is a possible role for cell-mediated immunity, but repeated environmental exposure does not elicit protective humoral or cellular immunity. A vaccine is under development, but economic constraints may make vaccination an unrealistic option for many regions of endemicity. Disease manifestations are protean, and no inexpensive, practical, and accurate rapid diagnostic tests are commercially available; diagnosis relies on culture of the organism. Despite the introduction of ceftazidime- and carbapenem-based intravenous treatments, melioidosis is still associated with a significant mortality attributable to severe sepsis and its complications. A long course of oral eradication therapy is required to prevent relapse. Studies exploring the role of preventative measures, earlier clinical identification, and better management of severe sepsis are required to reduce the burden of this disease.
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Affiliation(s)
- Allen C Cheng
- Menzies School of Health Research, Charles Darwin University, Darwin, Australia
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Sprague LD, Neubauer H. Melioidosis in animals: a review on epizootiology, diagnosis and clinical presentation. ACTA ACUST UNITED AC 2005; 51:305-20. [PMID: 15525357 DOI: 10.1111/j.1439-0450.2004.00797.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Melioidosis, an infectious disease caused by Burkholderia pseudomallei is an emerging disease with high impact on animals and man. In different animal species, the clinical course varies and delayed diagnosis poses risks for the dissemination of the agent in non-endemic areas. Not only migration and transport of animals around the world but also tourism increases the risk that melioidosis can leave its endemic boundaries and establish itself elsewhere. Detection of the agent is a major challenge, as the agent has to be handled in laboratories of biosafety level 3 and test kits are not yet commercially available. Veterinarians and doctors should be aware of melioidosis not only as an agent of public interest but also in terms of a bioterrorist attack. The aim of this review is to describe the agent, its aetiology, the manifestation in a variety of animal species as well as to describe diagnostic procedures, typing techniques and countermeasures.
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Affiliation(s)
- L D Sprague
- Klinik und Poliklinik für Strahlentherapie und Radiologische Onkologie der TU München, Klinikum rechts der Isar, Ismaningerstr. 22, 81675 München, Germany.
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Abstract
PURPOSE OF REVIEW Burkholderia pseudomallei, the causative agent of melioidosis and a potential biological weapon, is still unfamiliar in some areas where sporadic cases are being reported among travelers. This review highlights findings in 2002-2003 and is an extension of a recent review by Dance. RECENT FINDINGS The allele profiles of B. pseudomallei are distinguishable from avirulent Burkholderia thailandensis, but Burkholderia mallei is a clone of B. pseudomallei. Capsule and a type III protein secretion apparatus enable B. pseudomallei to survive intracellular killing and facilitate intercellular spread. A strong antibody response to infection is useful for monitoring disease activity. A mutant that is auxotrophic in the branched chain amino acid biosynthetic pathway has been found to be attenuated and protective. A new selective media is useful for isolation from contaminated specimens and the environment. Molecular techniques have been developed to distinguish B. pseudomallei from B. thailandensis and B. mallei as well as for serological diagnosis. Classification of the clinical manifestation is proposed to facilitate global communication, and will be useful to compare the efficacies of new regimens and adjunctive immunomodulatory therapies, such as granulocyte colony-stimulating factor and activated protein C for septicemic melioidosis. SUMMARY Study of pathogenesis and intracellular survival of B. pseudomallei is advancing and may lead to better methods of therapy and vaccine production. New antimicrobial agents and immunomodulators are being studied to shorten the duration of treatment in the acute and maintenance phases, reduce the high mortality rate in septicemic melioidosis, and prevent relapses.
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Affiliation(s)
- Amorn Leelarasamee
- Division of Infectious Diseases and Tropical Medicine, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkoknoi, Bangkok 10700, Thailand
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